Cross-flow-Who was first?

Sir,

Surely you are mistaken in stating that Peugeot were the pioneers of cross-flow heads in 1955 (MS September p.964). What about the excellent head of the Aprilia designed in 1936, a diagram of which I enclose showing the arrangement of the ports, looking up into the head from below.

To the best of my knowledge, Lancia have never claimed to be first to introduce this form of head, so possibly there were others even before this.

Grant Gibson – London, N6.

[A twin-cam head and T-head were always “cross-flow” and there may well have been others, not using these valve locations, which pre-dated the Lancia Aprilia. Any views anyone ?—Ed.]